connection to the public Internet. This no coupling alternative omits the need for interworking standardization. For majority of the web traffic there is no added value to route the data through the operator core network. In this case the offloading can simply be carried out by switching the IP traffic to use the Wi-Fi connection in mobile client instead of the cellular data connection. In this approach the two networks are in practice totally separated and network selection is done by a client application. Studies show that significant amount of data can be offloaded in this manner to Wi-Fi networks even when users are mobile.Kyunghan Lee, Joohyun Lee, Yung Yi, Injong Rhee and Song Chong. Mobile Data Offloading: How Much Can WiFi Deliver? Proc. CoNEXT 2010 However, offloading does not always mean reduction of resource consumption (required system capacity) in the network of the operator. Under certain conditions and due to an increase of the burstiness of the non-offloaded traffic (i.e. traffic that eventually reaches the network of the operator in a regular way), the amount of network resources to offer a given level of QoS is increased. In this context, the distribution of offloading periods turns out to be the main design parameter to deploy effective offloading strategies in the network of MNOs making non-offloaded traffic less heavy-tailed, hence reducing the resources needed in the network of the operator.. The energy consumption in offloading is also another concern. Initiation of offloading procedure There are three main initiation schemes: WLAN scanning initiation, user initiation and remotely managed initiation. In the WLAN scanning-based initiation the user device periodically performs WLAN scanning. When a known or an open Wi-Fi network is found, an offloading procedure is initiated. In the user-initiated mode, a user is prompted to select which network technology is used. This happens usually once per a network access session. In the remotely managed approach, a network server initiates each offloading procedure by prompting the connection manager of a specific user device. Operator-managed is a subclass of the remotely managed approach. In the operator-managed approach, the operator is monitoring its network load and user behavior. In the case of forthcoming network congestion, the operator initiates the offloading procedure. ANDSF Access network discovery and selection function (ANDSF) is the most complete 3GPP approach to date for controlling offloading between 3GPP and non-3GPP access networks (such as Wi-Fi). The purpose of the ANDSF